This book provides documented county distribution data on the vascular flora of the Glaciated Allegheny Plateau region of Ohio. The flora includes 2,002 species and 27 in terspecific hybrids belonging to 706 genera and 148 families. For each taxon cited, county occurrences are indicated by two-letter acronyms. Taxa are presented in a catalogue format and nomenclature generally follows Gray’s Manual of Botany, 8th Edition.